Interactive ads can leak user traits, study shows 0.65 AUC inference risk
A new arXiv paper demonstrates that when ad platforms expose which user clicked an interactive targeted ad, advertisers can infer sensitive attributes with up to 0.65 AUC using Bayesian and supervised attacks. The authors provide a benchmark, simulator, and show that aggregate reporting and randomized disclosure curtail the leakage. This highlights a concrete privacy flaw in current ad systems.